Marine Weather and TidesLivermore, CA

Version 3.4

What's New / NOTES
3/3/2018 - There is a new GOES Satellite for the east coast that required rewriting that part of the code. Please report any issues.
6/25/2017 - NOAA is having a major issue that impact the 7 day forecast load times. Many users are reporting problems. The issue has been reported.
5/23/2017 - Worked with NOAA again to speed up the 7 day forecast load times. Thanks to them for being responsive.

Sunrise 7:08AM

Sunset 7:20PM

Monday March 19, 2018 8:52 PM PDT (03:52 UTC)

Moonrise 7:42AM

Moonset 8:45PM

Illumination 11%

NOTE: Some of the data on this page has not been verified and should be used with that in mind. It may and occasionally will, be wrong. The tide reports are by xtide and are NOT FOR NAVIGATION.

PZZ530 San Pablo Bay Suisun Bay The West Delta And San Francisco Bay North Of The Bay Bridge- 246 Pm Pdt Mon Mar 19 2018 .small craft advisory in effect from Tuesday afternoon through late Tuesday night... Tonight..SE winds 10 kt. Tue..E winds 5 to 15 kt...increasing to 15 to 25 kt in the afternoon. Chance of rain in the morning, then rain likely in the afternoon. Tue night..E winds 5 to 15 kt. Rain in the evening, then chance of rain after midnight. Wed..S winds 5 to 15 kt. Chance of rain in the morning, then rain likely in the afternoon. Wed night..S winds 15 to 25 kt. Rain likely. Thu..W winds 5 to 15 kt. Showers likely and slight chance of Thunderstorms, then slight chance of showers. Fri..SW winds 5 to 15 kt. Slight chance of showers in the morning, then chance of showers in the afternoon. Sat..W winds 10 kt. Slight chance of showers.

PZZ500 246 Pm Pdt Mon Mar 19 2018 Synopsis for the central california coast and bays including the Monterey bay..Greater farallones...and cordell bank national marine sanctuaries... Winds will increase from the south to southeast over the coastal waters and bays starting Tuesday morning as a strong warm front arrives from the southwest. Showers and possibly Thunderstorms will affect the coastal waters and bays Tuesday through Saturday morning. Freshly steepening mixed seas develops Tuesday through Thursday, creating rough and erratic seas.

Synopsis Look for dry weather conditions and slightly warmer
temperatures Monday. A system will then arrive on Tuesday bringing
widespread rainfall to our region through Thursday with periods
of heavy rain and locally strong southerly winds. Showers then
linger into Friday and Saturday before drying conditions return
late in the forecast period.

Discussion As of 01:50 pm pdt Monday... Nice march day as
temperatures warmed into the 50s and 60s around the bay area.

All eyes now focus on a robust storm system currently spinning
over the eastern pacific near 140.5w 33n. This storm system will
begin to pump subtropical moisture to ca as an atmospheric
river. Source region is near hi so this ar can be described as a
pineapple express. Latest satellite imagery has pwats 1.5-2" or
about +200% of normal.

Models have remained rather consistent bringing the first moisture
push to the region early Tuesday. Light to moderate rain is on
track to develop Tuesday morning along the big sur coast and then
spread northward through the day. As light to moderate rain
spreads north, moderate to heavy rain is expected to develop over
the big sur coast santa lucias Tuesday afternoon as low level
increases and higher pwats slam into 5k ft peaks. The moderate to
heavy rain will likely cause some minor hydro issues along the big
sur coast with creek rises, ponding and possible low end flooding
at this time. The lower confidence part of the forecast is where
this intense plume of moisture sets up. Current forecast model
guidance keeps it at big sur, but if it shifts just 30-50 miles
north it could be a different ballgame and santa cruz mts could
get dumped on. That solution is less likely, but still wanted to
mention it. Winds will also increase out of the south Tuesday into
Wednesday. Winds will be strongest along the coast and higher
coastal peaks with gusts 30-40 mph.

The main moisture plume begins to shift slowly southward Tuesday
night as the low pressure begins to move eastward. Rain intensity
will decrease across the bay are as it shifts toward socal, but
light to moderate rain will continue Tuesday night into Wednesday.

Rainfall will increase again on Wednesday as another impulse comes
off the pacific. One change to the forecast on Wednesday was to
include a slight chance for thunder during the afternoon evening
as the airmass becomes slightly unstable. Sfc CAPE is weak, but
soundings show a little instability to warrant at least a
mention. Best chance will be across the east south bay and
locations southward. Moderate to heavy rain will be possible
Wednesday night into early Thursday as a cold front begins to
move into the bay area. Thunderstorm chances return again on
Thursday with the passage of the cold front. Latest guidance
shows even more instability than Wednesday, especially the
central valley (500 j kg CAPE for the bay area, which is pretty
solid). Given how moist the atmosphere is any developed
thunderstorm will be capable of producing localized heavy rain.

Thunderstorms combined with an already wet ground could result in
flooding. Moderate to heavy rain rain will finally begin to
diminish from NW to SE late in the day Thursday. Lingering showers
will be possible Friday and even into Saturday as the core of the
mid upper level system pushes inland into the pacific northwest.

Heaviest rainfall is still slated for Tuesday morning through
Thursday morning with pulses of moisture. Only minor tweaks to
previous rainfall, but big sur coast will see the most. Rainfall
amounts are anticipated to range from 0.75" to 1.50" in most urban
areas with 1.00" to 3.00" in the north bay and santa cruz
mountains and 2.00" to 5.00" in the santa lucia mountains above
the big sur coast. Could see isolated amounts upwards of
8.00-10.00" along the southwest facing coastal slopes of monterey
county (mining ridge chalk peak).

Simply put this event will be interesting to watch. It will be an
ar orographic event initially and then transition to a convective
event with the frontal boundary. Please pay attention to the
weather the next few days as there is potential for hazardous
conditions.

Drier conditions appear to develop Saturday into Sunday region-wide
as a weak ridge of high pressure builds over the eastern pacific. At
this time, dry conditions with temperatures near seasonal averages
look likely for the final week of march.

Aviation As of 5:30 pm pdt Monday... Conditions will remainVFR
through tonight with high clouds. Deeper moisture arrives Tuesday
morning. Models have been trending slower on the timing and it
now looks like the rain and lower CIGS do not arrive until after
18z in the mry bay area and 20z for the sfo bay area.

Southeast winds increase but strongest winds remain along the
coast and over the waters.

Monterey bay terminals...VFR. Light rain after 18z with cigs
lowering to 4000 ft. Winds becoming SE and increasing to 15-18 kt
with gusts to 22-24 kt in the salinas valley.

Marine As of 04:04 pm pdt Monday... Winds will increase from the
south to southeast over the coastal waters and bays starting
Tuesday morning as a strong warm front arrives from the
southwest. Showers and possibly thunderstorms will affect the
coastal waters and bays Tuesday through Saturday morning. Freshly
steepening mixed seas develops Tuesday through Thursday, creating
rough and erratic seas.

Mtr watches warnings advisories Tngt None.

Public forecast: mm
aviation: W pi
marine: bam canepa
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Weather Reporting Stations

EDIT(on/off) &nbspHelpNOTE: Click on distance to see the station location on a map

Weather Map and Satellite Images

(on/off) &nbspHelpWeather MapGOES Local Image of CentralWestCoastEDITNOTE: East coast views moved to GEOS-16. They are experimental and not well supported by NOAA so they may not be correct so be warned. This change required redoing a large amount of the GOES code. If the image you are expecting is not showing, please let me know. You may need to use the EDIT function to update your location.Link to LoopOther links:
Northern PacificContential USFull GOES-East

Wind Forecast for San Francisco/Monterey Bay Area, CA (23,6,7,8)

Disclaimer:The information on this web site has not been checked for accuracy. It is for entertainment purposes only and should be independently verified before using for any other reason. There are five sources. 1) Documents and manuals from a variety of sources. These have not been checked for accuracy and in many cases have not even been read by anyone associated with L-36.com. I have no idea of they are useful or accurate, I leave that to the reader. 2) Articles others have written and submitted. If you have questions on these, please contact the author. 3) Articles that represent my personal opinions. These are intended to promote thought and for entertainment. These are not intended to be fact, they are my opinions. 4) Small programs that generate result presented on a web page. Like any computer program, these may and in some cases do have errors. Almost all of these also make simplifying assumptions so they are not totally accurate even if there are no errors. Please verify all results. 5) Weather information is from numerious of sources and is presented automatically. It is not checked for accuracy either by anyone at L-36.com or by the source which is typically the US Government. See the NOAA web site for their disclaimer. Finally, tide and current data on this site is from 2007 and 2008 data bases, which may contain even older data. Changes in harbors due to building or dredging change tides and currents and for that reason many of the locations presented are no longer supported by newer data bases. For example, there is very little tidal current data in newer data bases so current data is likely wrong to some extent. This data is NOT FOR NAVIGATION. See the XTide disclaimer for details. In addition, tide and current are influenced by storms, river flow, and other factors beyond the ability of any predictive program.